What is Foundation Underpinning?
In the world of construction, underpinning is the process of reinforcing a home or building’s failing foundation. The process of underpinning takes place in sections so as not to compromise the integrity of the structure all at once.
There are several different reasons foundations fail. The original foundation could be deteriorated due to time and elements in the soil. The original foundation could be cracking because of changes in the soil such as water pressure, temperature, or even a nearby excavation of a tree. Foundations can be weakened when load is added to buildings during renovations.
There are many reasons why foundation underpinning might be warranted. The important thing to know is that there are solutions. The quicker symptoms of foundation failure are identified, the easier and less expensive the repair will be. Turning a blind eye to signs of foundation failure will compromise the complete integrity of the structure it supports, deteriorate property value, and cause risks to the structure’s inhabitants.
The type of underpinning we do most often at AMC911 is referred to as “mini-piled underpinning” and we accomplish it with push piers and helical piers.
Deep Driven Steel Resistance Push Piers by AMC911
Unlike any other foundation repair company in Hampton Roads, AMC911 offers a deep driven piering solution to the outside of the structure (eccentric pier) as well as to the inside of the structure in a crawl space application (concentric pier). This is important on a number of levels because of the nature of the soil in Hampton Roads.
Deep driven piers are necessary for the restoration of a sinking foundation. Hampton Roads ranks second only to New Orleans as cities most prone to damage caused by sea level rising in the country. According to the World Resources Institute, while there are several causes of sea level rise in Hampton Roads, “land sinkage” is the main culprit. Scientists and research has proven our area is sinking on average 1 inch lower every 10 years.
The only permanent solution to soil failure that is common across the 757 is a foundation underpinning solution that incorporates deep driven steel push piers. Push piers are also called “resistance piers” because they are driven using hydraulics into the earth until the point of resistance.
Push piers by AMC911 will provide a permanent solution to settlement of a home or commercial structure because they will not be affected by additional changes in the ground below your house. This is why we use this method of repair for structures settling due to bad soil. Push pier underpinning is the most reliable repair method there is… There’s no debating it!
Another Option for Underpinning… Crawl Space Push Piers by AMC911
In addition to push piers to support the foundation wall, AMC911 offers a push pier application on the inside of the crawl space. The AMC911 deep driven crawl space pier is essentially our “dragon in the closet” because we are the only company in Hampton Roads that offers it. The AMC911 crawl space push pier is designed to lend a true lift, unlike crawl space jacks which are intended mainly for stabilization. The AMC911 deep driven crawl space pier is engineered to provide lift in a crawl space when the structure is settling due to soil failure.
Our crawl space push pier is driven into the earth using the weight of the structure and hydraulic pressure until the load is transferred to more suitable soil. This pier is typically driven off of the main girder beams of the structure.
This pier was engineered to be the strongest foundation pier in the industry. It’s 100% galvanized steel and it’s installed centrally beneath the footing versus the outside of the foundation footing. This installation concept is unique… The load of the structure is shifted directly on top of the pier bracket. This is called a “concentric lift.” This piering application will lend permanent stabilization compared to a crawl space jack that will warrant constant adjustment as soil conditions change over time.
Concrete Underpinning by AMC911
Concrete underpinning has been used for centuries in foundation repair. Concrete underpinning differs from push pier underpinning in that it is strictly intended to increase the size of the structure’s existing deteriorated foundation, hence strengthening it in the process.
Concrete underpinning incorporates the use of rebar. The purpose of rebar is to reinforce the concrete and prevent cracking in the concrete. Rebar is encased in concrete at least 3 inches on all sides. Rebar widens the footprint of the supplemental concrete.
Which Underpinning Method is Best?
The condition of the soil your home sits on will determine the method of foundation underpinning repair. Every situation is different. But if your home feels like it’s “sinking,” you have soil failure. If you have soil failure, you need a deep driven pier underpinning solution.
Something like this prefabricated rebar cage combined with a supplemental concrete footer is not suited for foundation repair in all ground conditions. In fact, it’s not advised for homes that suffer settling due to soil failure. Concrete is heavy, so adding more weight to already compromised soil beneath your home is not advisable.
Subsidence can occur at varying degrees across neighborhoods in Hampton Roads. Foundation underpinning is only necessary when that subsidence is vigorous and ongoing. Our team of experts will not only lend you a free inspection of the soils around your home and how they are affecting your home, but we’ll offer a solution that’s targeted to your home’s unique needs.